António Casimiro

The Timely Computing Base

Paulo Veríssimo and António Casimiro

Fast Abstract at the 29th Annual International Symposium on Fault-Tolerant Computing, Madison, Wiscosin, USA, June 1999


A large number of the emerging services have interactivity or mission-criticality requirements, which are best translated into requirements for fault-tolerance and real-time.
To implement these services a given distributed systems model must be chosen. However, we have to face the following problem: fully asynchronous models do not satisfy our needs, because they do not allow timeliness specifications; on the other hand, correct operation under fully synchronous models is very difficult to achieve (if at all possible) in large-scale infrastructures, since they have poor baseline timeliness properties. Then, what system model to use for applications with synchrony (i.e. real-time) requirements running on environments with uncertain timeliness?
We propose a framework that describes the problem in a generic way. We call it the Timely Computing Base (TCB) model. A detailed description of the TCB model can be found in [Verissimo:99a].


  author       = "Ver\'{i}ssimo, P. and Casimiro, A.",
  title        = "The {T}imely {C}omputing {B}ase",
  booktitle    = "Supplemental Volume of the Digest of Papers: FTCS-29, The Twenty-Ninth Annual
                  International Symposium on Fault-Tolerant Computing",
  year         = "1999",
  abstractURL  = "",
  documentURL  = "",
  pages        = "",
  publisher    = "IEEE Computer Society",
  address      = "Madison, Wiscosin, USA",
  month        = jun


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